package BC124_小乐乐是否被叫家;

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double sum = 0;
        for (int i = 0; i < 3; i++){
            sum += sc.nextDouble();
        }
        double avg = sum / 3;
        if (avg >= 60){
            System.out.println("NO");
        }else {
            System.out.println("YES");
        }
    }
}
